Avalanche Forecast

Issued: Nov 27th, 2022 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs.

mconlan, Avalanche Canada

Kootenay Boundary, Shuswap, North Okanagan, Whatshan, Bonnington, Kootenay Pass, Rossland, South Okanagan, Ymir.

Recent snow overlies various layers that could produce slab avalanches. A cooling trend may decrease the potential of them being triggered, but not eliminate it.

Summary

Confidence

Moderate

Avalanche Summary

A few small avalanches were observed in the south, as described in this MIN.

Looking forward, avalanche activity may decrease with a cooling trend, but the possibility of triggering the mid-November layer remains, particularly where the snowpack is smooth and uniform.

Snowpack Summary

Early season conditions exist with low snow amounts and crusts found at lower elevations and a deeper and drier snowpack approaching 1 m at treeline and alpine elevations.

Around 30 cm of snow overlies a weak layer that formed mid-November that consists of sugary faceted grains, weak surface hoar crystals in sheltered terrain features, and a hard crust on steep sun-exposed slopes.

The remainder of the snowpack is faceted as shown in this MIN, but is likely still intermixed with rocks, brush, and trees.

Weather Summary

Sunday Night

Partly cloudy with isolated flurries, accumulation 1 to 3 cm, 10 km west wind, treeline temperature -10 C.

Monday

Mix of sun and cloud with isolated flurries, accumulation 1 to 3 cm, 10 km/h northeast wind, treeline temperature -13 C.

Tuesday

Increasing cloud with isolated afternoon flurries, accumulation 1 to 3 cm, 20 km/h south wind, treeline temperature -16 C.

Wednesday

Cloudy with snowfall, accumulation 10 to 20 cm, 40 km/h south wind, treeline temperature -10 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
Closely monitor how the new snow is bonding to the old surface.
Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.

Problems

Storm Slabs

Around 30 cm of recent snow overlies various layers formed mid-November, including surface hoar, faceted grains, and a hard crust. The recent snow may not bond well to these layers.

Wind may have redistributed the storm snow at high elevations, forming isolated wind slabs in lee terrain features.

Avalanche hazard is unlikely anywhere snowpack depths have yet to overcome ground roughness like brush and rocks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Nov 28th, 2022 4:00PM